EP0071385B1

EP0071385B1 - Terminal assembly for circuit interrupter

Info

Publication number: EP0071385B1
Application number: EP82303793A
Authority: EP
Inventors: Shigemi Tamaru; Yasushi Room No.111 Genba; Takayoshi Ishikawa; Kiyoshi Eguchi; Hideshi Takashita
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 1981-07-17
Filing date: 1982-07-19
Publication date: 1985-12-04
Also published as: KR840000821U; IN157892B; JPS5813655U; EP0071385A2; AU8610782A; KR860003608Y1; DE3267792D1; US4468082A; JPH019086Y2; EP0071385A3; AU541261B2

Description

This invention relates to a terminal assembly for a circuit interrupter, and more particularly to a terminal assembly used with a circuit interrupter to connect a plurality of source terminals and a plurality of load terminals of a circuit interrupter to external electric conductors respectively.
High capacity circuit interrupters generally include the terminal assembly having a structure extremely strong and good in electric insulation because such circuit interrupters generally produce the high electromagnetic force upon the occurrence of a shortcircuited current. A general form of conventional terminal assemblies disposed on high capacity circuit interrupter has comprised a plurality of source terminals connected to circuits on the source side within the particular circuit interrupter and also to external electric conductors respectively, and a plurality of load terminals connected to circuits on the load side within the circuit interrupter in respectively, the arrangement being so that those source terminals oppose to associated ones of the load terminals, one pair of opposite source and load terminals for each of the phases of the circuit interrupter. For example, the terminal assembly for three phase circuit interrupter includes three pairs of source and load terminals disposed in parallel to one another thereon. Then the plurality of the source and load terminals pairs have alternated electrically insulating side plates whose number is larger one than that of the terminal pairs after which a pair of metallic plates are disposed on the outer sides of the outermost side plates respectively. Subsequently a plurality of bolts have been extended through the metallic and side plates and fastened to the metallic plates by means of nuts thereby to fix the source and terminals to one another.
From the foregoing it is seen that in the conventional terminal assembly, the source terminals, the load terminals and the side plates are collected into separate units each including a plurality of the components and that, after their assembling, the components are connected together into a unitary structure by bolt and nut means.
Thus conventional terminal assemblies such as described above have been disadvantageous in that the assembling operation thereof is extremely difficult, and there is a fear that the source and load terminals may damage the components adjacent thereto due to magnetic forces developed thereon and others because those terminals are permitted only to be fixed on the relatively short portion to the associated side plates.
Accordingly it is an object of the present invention to provide a new and improved terminal assembly for a circuit interrupter capable of being easily assembled and including a plurality of source terminals and a plurality of load terminals prevented from shifting due to the magnetic force developed thereon and others.
The present invention provides a terminal assembly for a circuit interrupter comprising a plurality of source terminals one for each of phases of the circuit interrupter, a plurality of load terminals disposed opposite the source terminals respectively, a plurality of pairs of first and second side plates, each having in a front surface thereof a pair of parallel grooves for fitting onto lateral surfaces of the opposite source and load terminals respectively, and bolts extending through the first and second side plates to hold these and the terminals in position, wherein a respective supporting bar is provided for fixing end portions of each pair of opposite source and load terminals.
In a preferred embodiment of the present invention each pair of the opposite source and load terminals are carried by one pair of the first and second side plates by having further a raised and a recessed portion on either of the lateral surfaces of each of the opposite source and load terminals fitted into and onto a recessed and a raised portion on the front surface of each of the first and second side plates and connected to adjacent pairs of the opposite source and load terminals through different pairs of the first and second side plates connected back to back to each other, the plurality of opposite source and load terminals and the plurality of first and second side plates are put in a unitary structure between a pair of metallic plates through a pair of bolts extending through the plurality of first and second side plates and the pair of metallic plates, and each of the supporting bars includes a pair of notches fitted onto the lateral surfaces of end portions of a mating pair of the opposite source and load terminals and is disposed on a lateral surface of an associated one of the first and second side plates, so that the outermost supporting bar is fixedly secured to an adjacent one of the metallic plates through a lateral locking metallic member and each pair of the intermediate supporting bars are connected back to back to each other and fixedly connected to the connected first and second side plates through an intermediate locking metallic member.
The present invention will become more readily apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

Figure 1 is a side elevational view, partly in section of one embodiment according to the terminal assembly of the present invention used with a circuit interrupter with a part cutaway and with parts omitted;
Figure 2 is a perspective view of the arrangement shown in Figure 1 with parts illustrated in an exploded view and with parts omitted;
Figure 3 is a front plan view of the arrangement shown in Figure 1;
Figure 4 is a perspective view of the source terminal shown in Figures 1, 2 and 3;
Figure 5 is a perspective view of the load terminal shown in Figures 1, 2 and 3;
Figure 6A is a front view of the first side plate shown in Figures 1, 2 and 3;
Figure 6B is a side elevational view of the arrangement shown in Figure 6A;
Figure 6C is a rear plan view of the arrangement shown in Figure 6A;
Figures 6D, and 6E are cross sectional views of the arrangement shown in Figure 6 with the cross sections taken along the lines Vld-Vld and Vie-Vie of Figure 6A respectively;
Figure 6F is a side elevational view of the outermost one of the first side plates shown in Figures 2 and 3;
Figure 6G is a rear plan view of the arrangement shown in Figure 6F;
Figure 7A is a rear plan view of the second side plate shown in Figures 1, 2 and 3;
Figure 7B is a side elevational view of the arrangement shown in Figure 7A;
Figure 7C is a front plan view of the arrangement shown in Figure 7A;
Figures 7D and 7E are cross sectional views of the arrangement shown in Figure 7A with the cross sections taken along the lines Vlld-Vlld and V!)e―V!)e of Figure 7C;
Figure 7F is a rear plan view of the outermost one of the second side plate shown in Figures 2 and 3;
Figure 7G is a side elevational view of the arrangement shown in Figure 7F;
Figure 8A is a front plan view of the supporting bar shown in Figure 2;
Figures 8B and 8C are side elevational views of the arrangement shown in Figure 8A as viewed on the lefthand and righthand sides thereof in Figure 8A respectively;
Figure 8D is a rear plan view of the arrangement shown in Figure 5;
Figure 9A is a front plan view of the lateral locking metallic member shown in Figures 2 and 3;
Figure 9B is a side elevational view, partly in section of the arrangement shown in Figure 9A;
Figure 10A is a plan view of the intermediate locking metallic member shown in Figures 2 and 3; and
Figure 10B is a side elevational view, partly in section of the arrangement shown in Figure 10A.

Description of the Preferred Embodiment

Referring now to Figures 1, 2 and 3 of the drawings, there is illustrated one embodiment according to the terminal assembly of the present invention used with a three phase interrupter. The arrangement illustrated comprises a plurality of strip-shaped source terminals 10, in this case, three source terminals one for each phase of the circuit interrupter, disposed in predetermined equal intervals in a common plane, and a plurality of strip-shaped load terminals 20 equal in both width and thickness to the source terminals, 10 in this case, three load terminals disposed in the same manner as the source terminals 10 thereunder as viewed in Figures 2 and 3 one for each source terminal 10 to be opposite and parallel to the source terminals 10 respectively. Thus in the example illustrated the three source terminals 10 and the three load terminals 20 are arranged in two rows and three columns. Then a pair of first and second side plates 30 and 40 respectively formed into a common rectangular shape (see Figures 5 and 6) of an electrically insulating material are connected back to back to each other and interposed between each pair of adjacent source terminals 10 and also between each pair of adjacent load terminals 20 to run perpendicularly to the longitudinal axes of the source and load terminals 10 and 20. The leftmost source and load terminals 10 and 20 are engaged by another second side plate 40 in the same manner as the intermediate source and load terminals 10 and 20 while the rightmost source and load terminals 10 and 20 are engaged by another first side plate 30 in the same manner as the intermediate source and load terminals 10 and 20.
As shown in Figure 3 and best in Figure 1, a through type current transformer 50 is fitted onto the central portion of each source terminal 10. The current transformer 50 includes an iron core 500 formed into a rectangle of a stack of silicon steel laminations and a pair of secondary windings 502 disposed around a pair of opposite legs of the iron core and connected to each other as shown best in Figure 2 to produce thereacross a secondary current proportional to a primary current flowing through the mating source terminal 10.
A supporting bar 60 of an electrically insulating material is disposed to carry each of lateral surfaces of those extremities shown in Figure 2 as being nearer to the viewer of the source and load terminals 10 and 20 arranged in each column.
Figure 4 shows the details of the source terminal. As shown, the source terminal 10 includes a pair of threaded holes 100 adjacent to one end nearer to the viewer which holes are also shown in Figures 1 and 2, and a stationary contact 102 disposed at the other end thereof. Thus the source terminal 10 is arranged to be connected at the one end to an associated external electric conductor (not shown) by having a pair of screws (not shown) screw threaded into the holes 100 and separably connected at the other end to a mating movable electric conductor (not shown) included in a source circuit (not shown) within the circuit interrupter by having the stationary contact 162 separably engaging a movable contact (not shown) disposed at the end of the movable electric conductor.
Further the source terminal 10 includes a pair of U-shaped recesses 104 disposed in opposite relationship on both lateral surfaces 106 to leave respective U-shaped raised face 106 between the recesses 104 and that end thereof bearing the stationary contact 102 for the purpose as will be apparent hereinafter.
Figure 5 shows the details of load terminal 20. The arrangement illustrated includes a pair of threaded holes 200 disposed adjacent to one end thereof nearer to the viewer which holes are also shown in Figure 1 and a groove 202 disposed on . the surface of the other end thereof to extend throughout its width. Thus the load terminal 20 is arranged to be connected at one end to an associated external electric conductor by having a pair of screws (not shown) screw threaded into the holes 200 and at the other end to an associated flexible electric conductor included in a load circuit (not shown) of the circuit interrupter by inserting the end of the flexible electric conductor into the groove 202 (see Figure 1).
In other respects the arrangement of Figure 5 is identical to that shown in Figure 4 excepting that the former is longer than the latter by about the depth of the groove 202. Therefore the components of the arrangement shown in Figure 5 are designated by the same reference numerals identifying the corresponding ones of those shown in Figure 4 with the prefix 2. For example, the reference numeral 204 designates a recess on the lateral surface 206 of the arrangement shown in Figure 5 to correspond to the recess 104 shown in Figure 4.
As described above, the three source terminals 10 and the three load terminals 20 for the phases A, B and C are arranged in two rows and three columns and held in place by the pair of the first and second side plates 30 and 40 interconnected back to back and interposed between each pair of adjacent columns with the outermost first and second side plates 30 and 40 engaged by the outmost pairs of the source and load terminals 10 and 20 respectively whereby the pair of terminals 10 and 20 for each phase are physically isolated and electrically insulated from each other and from the remaining terminals 10 and 20 for the other phases.
Figures 6 and 7 show the details of the first and second side plates 30 and 40 respectively. As shown in Figure 6A wherein there is illustrated the front surface of the first side plate 30, the latter is of a generally rectangular shape and includes a pair of U-shaped positioning grooves 300 and 302 extending at a predetermined interval from one longer side of the rectangle perpendicularly thereto and terminating a predetermined equal distances from that longer line. Also the grooves 300 and 302 are equal distant from a lens perpendicular to the longer side of the rectangle and passing through the center thereof. However the groove 300 opens on the center of a U-shaped recess 304 disposed on the longer side of the rectangle to be deeper than the groove 300 (see Figure 6E). The recess 304 has a dimension sufficient to accommodate one lateral portion of the through type current transformer 50 shown in Figures 1, 2 and 3. Each of the grooves 300 or 302 is aligned with a U-shaped recess 310 or 312 shown in Figure 6A as being square, and lengthwise thereof through a spacing 306 or 308 shown in Figure 6A as being rectangular (also see Figures 6D and 6E).
The groove 300 and the recess 310 are so dimensioned that the groove 300 and the recess 310 are firmly fitted onto that portion of the lateral surface of the source terminal 10 near to threaded holes 100 and the raised face 108 thereof respectively and that the spacing 306 forms a raised portion which is firmly fitted into the recess 104 of the source terminal 10.
Similarly the groove 302 and the recess 312 are so dimensioned that the groove 302 and the recess 310 are firmly fitted onto that portion of the lateral side of the load terminal 20 near to the threaded holes 200 and the raised face 108 thereof respectively and that the spacing 306 forms a raised portion which is firmly fitted into the recess 204 of the load terminal 20.
Also a pair of spaced circular holes 314 and 316 extend through the first side plate 30 adjacent to the diagonal thereof between the grooves 300 and 302 for the purpose as will be apparent later.
Further a U-shaped notch 318 is provided at the center of that longer side of the rectangle in which the recesses 302 and 304 open and a short groove 320 of a semicircular cross section extends from the center of the bottom of the notch 318 on the rear surface of the first side plate 30 as shown best in Figure 6C. Then a semi-hexagonal nut 322 is buried in the side plate 30 adjacent to the notch 318 so that it includes cut ends flush with the rear surface and a threaded surface exposed to the semicircular groove 320 and engageable by a bolt (not shown) inserted into the recess 318 and the . groove 320. The purpose of the notch 318, the groove 320 and the nut 322 will be apparent hereinafter.
That first side plate 30 disposed on the outermost side or the rightmost side as viewed in Figure 2 has the details as shown in Figures 6F and 6G wherein there are illustrated the longer side and rear surfaces thereof respectively. The arrangement illustrated is different from that shown in Figures 6A, 6B, 6C, 6D and 6E only in that in Figures 6F and 6G a rectangular shallow recess 324 is disposed on the rear surface of the first side plate 30 to be aligned with and identical in width to the notch 318 with the omission of the semicircular groove 320 and the semi-hexagonal nut 322.
Thus the components on the outermost first side plate 30 are designated by the same reference numerals identifying the corresponding components on the intermediate first side plate 30. For example, the reference numeral 304 designates a recess on the outermost first side plate 30 for the through type current transformer 50.
From the comparison of Figures 6A, 6B, 6C, 6D and 6E with Figures 7C, 7B, 6E, 6D and 7A it will readily be understood that the second side plate 40 is a mirror image of the first side plate 30 with respect to a mirror (not shown) disposed in parallel to the front or rear surface thereof. Thus the components on the second side plate 40 are designated by the same reference numerals identifying the corresponding components on the first side plate 30 with the prefix 4. For example, the reference numeral 406 designates a spacing on the second side plate 40 arranged to be fitted into the recess 104 on the source terminal 10 as. a raised portion.
That second side plate 40 disposed on the outermost side or the leftmost side as viewed in Figure 2 has the details as shown in Figures 7F and 7G wherein there are illustrated the longer side and rear surfaces thereof. From the comparison of Figure 6F and 6G with Figures 7F and 7G it is seen that the outermost second side plate 40 is a mirror image of the outermost first side plate 30 with respect to a mirror (not shown) disposed in parallel to the front or rear surface thereof. Thus the components on the outermost second side plate 40 are designated by the same reference numerals identifying the corresponding components on the outermost first side plate 30 with the prefix 4. For example, the reference numeral 424 designates a shallow recess on the rear surface of the second outermost side plate 40.
Figure 8 shows the details of the supporting bar 60 for fixing those end portions of the source and load terminals 10 and 20 bearing the threaded holes 100 and 200 respectively wherein Figure 8A shows the front surface of the supporting bar 60, Figures 8B and 8C show the lefthand and righthand lateral surfaces thereof as viewed in Figure 8A and Figure 8D shows the rear surface thereof.
The supporting bar 60 has a width somewhat smaller than the thickness of the first or second side plate 30 or 40 for the purpose as will be apparent later and is provided on the lefthand lateral surface as viewed in Figure 8A with a pair of U-shaped notches 600 and 602 disposed at a predetermined interval corresponding to the distance between the opposite source and load terminals 10 and 20 to be fitted onto the righthand lateral surfaces 10 and 20 as viewed in Figures 4 and 5 of the terminals 10 and 20 respectively. Also the supporting bar 60 is provided on the righthand lateral surface as viewed in Figure 8A with three pairs of raised and recessed portions 604A and 604B, 606A and 606B and 608A and 608B located on the upper end portion, the central portion and the lower end portion respectively to be adjoined to each other. The raised portions 604A, 606A and 608A are identical to one another and the recessed portions 604B, 606B and 608B are also identical to one another. Further the raised portion is equal in both length and width to the mating recessed portion and has a height more or less greater than the depth of the latter. It is noted that, after having been turned through an angle of 180 degrees about the longitudinal axis thereof, the supporting bar 60 can engage the lefthand lateral surface as viewed in Figure 4 or 5 of the hole bearing end portion of each of the source and load terminals 10 or 20.
In order to assemble the source and load terminals 10 and 20 and the first and second side plates 30 and 40 into a unitary structure, a pair of first side plates 30 are connected back to back to the respective second side plate to prepare a pair of electrical insulations intended to be disposed between the phases A and B and between the phases B and C. Then the three source terminals 10 for the phases A, B and C are engaged by the outermost second side plates 40 disposed in opposite relationship with the first side plate 30 of one of the interconnected side plates and the last- mentioned first side plate 30, by the second side plate 40 of that interconnected side plates and the first side plate 30 of the other interconnected side plates and by the second side plate 40 of the other interconnected side plates and the outermost first side plate 30 disposed in opposite relationship with the latter respectively. To this end the lateral surfaces 106 of the source terminal 10 are fitted into the grooves 300 and 400 on the first and second side plates 300 and 400 on the first and second side plates 30 and 40 and the recessed portions 104 and the raised surfaces 108 on the lateral surfaces 106 of the source terminal 10 are fitted onto and into the raised portions 306 and 406 on the first and second side plates 30 and 40 respectively.
Subsequently the load terminals 20 are similarly engaged by the first and second side plates 30 and 40. At that time, the load terminal 30 has both the lateral surfaces 206 fitted into the grooves 302 and 402 on the first and second side plates 30 and 40 and the recessed portions 204 and the raised surfaces 208 on the lateral surfaces 206 thereof fitted onto and into the raised portions 308 and 408 recessed portions 312 and 412 on the first and second side plates 30 and 40 respectively.
Following this, a pair of metallic plates 70 and 72 are disposed in contact relationship on the outer surfaces of the outermost second and first side plates 40 and 30 respectively while a plurality of rectangular supporting members 74 (only two of which are illustrated only for purposes of illustration) are interposed between the metallic plates 70 and 72 and fastened to the latter by means of a pair of screws 76 one pair for each end of a different one of the supporting members 74.
Also a pair of bolts 78 and 80 extend through the holes 314 and 414 on the first and second side plates 10 and 20 aligned with one another and holes (not shown) on the metallic plates 78 and 80 aligned with the holes 314 and 414 respectively after which either end of each bolt 78 or 80 is inserted into a spring washer 82 and then screw threaded in a nut 80 and 84 until the source and load terminals 10 and 20 and the first and second side plates 30 and 40 are connected together into a unitary structure with the metallic plates 70 and 82 as shown in Figure 2.
Subsequently the through type current transformers 50 are extended through each of the source terminals 10 until they are accommodated in the U-shaped notches 304 and 404 on the first and second side plates 30 and 40.
Then attached to the metallic plate 70 is a lateral locking metallic member 86 as shown in Figure 9A and 9B. As shown, the lateral locking metallic member 86 is formed of an L-shaped strip including a protrusion 860 shown in Figure 9A as being square and disposed at the end of one leg, in this case, the vertical leg as viewed in Figure 9B of the L and a threaded hole 862 disposed on the intermediate portion of that vertical leg. The other leg 864 of the L includes a threaded hole 866 adjacent to the free end 868.
Referring back to Figure 2, the protrusion 860 of the lateral locking metallic member 86 is inserted into a hole 70A disposed on the metallic plate 70 to be located adjacent to the central recess 418 on the second side plate 40 contacted by the metallic plate 70. The lateral locking metallic member 86 is designed and constructed so that with the protrusion 860 inserted into the hole 70A the one leg is inserted into the recess 422 of the outermost second side plate 40 shown in Figure 7F or 7G, the threaded hole 862 is aligned with a hole 70B disposed on the metallic plate to be adjacent to the hole 70A, the other leg 864 is inserted into the notch 418 on the outermost second side plate 40, shown in Figures 7F and 7G to be flush with the exposed side surface of the side plate and the threaded hole 866 is aligned with through hole 610 on the supporting bar 60 which is later disposed on the exposed end surface of the that side plate 40. Then a screw 88 is threaded into the hole 70A on the metallic plate 70 with a spring washer 90 interposed therebetween and then screw threaded in the hole 862 on the lateral locking metallic member 86 resulting in the fixing of the lateral locking member 86 to the metallic plate.
Then another lateral locking metallic member 86 is fixed to the metallic plate 72 in the manner as described above.
Following this the supporting bar 60 is disposed on the end surface of the outermost second side plate 70 while the notches 600 and 602 thereon are fitted onto the lefthand lateral surface 166 and 206 of the source and load terminals 10 and 20 respectively and fixed to the lateral locking member 86 by means of a screw such as shown by the reference numeral 92 in Figure 2 threaded into a spring washer such as a spring washer 84 shown in Figure 2 and the through hole 610 thereon and then screw threaded into the threaded hole 866 on the lateral locking member 86. This results in the fixing of the supporting bar 60 to the lateral locking member 86.
The process as described above is repeated with the side of the metallic plate 72 to fix another supporting bar 60 to another lateral locking metallic member 86.
Subsequently a pair of supporting bars 60 interconnected back to back are fixed on each of the pairs of first and second plates 30 and 40 interconnected back to back and disposed between the phases A and B and between the phases B and C respectively. To this end, an intermediate locking metallic member 96 as shown in Figures 10A and 10B is inserted into the recesses 318 and 418 on the interconnected first and second side plates 30 and 40.
In Figures 10A and 10B the intermediate locking metallic member 96 is shown as being in the form of a rectangular strip including a central hole 960 and a pair of threaded holes 962 and 964 disposed adjacent to the central hole 960 to be aligned with one another on the longitudinal axis thereof. The intermediate locking member 96 is so dimensioned that it is inserted into the connected recesses 318 and 418 on the first and second side plate 30 and 34 interconnected back to back to fully fill those recesses and be flush the connected side surfaces of those side plates when disposed in those recesses 318 and 418, the intermediate locking member 96 has the central hole aligned with a nut formed of the two semihexagonal nuts 322 and 422 buried in the first and second side plates 30 and 40 and the threaded holes 962 and 964 aligned with the through holes 610 on the supporting bars 60 connected back to back to each other.
Therefore a screw 98 can be threaded into the central hole 960 on the intermediate locking member 96 flush with the side surfaces of the interconnected first and second side plates 30 and 40 and then screw threaded into the nut formed of semi-nuts 322 and 422 as described above. Thus the intermediate locking member 96 is fixed to the interconnected first and second side plates 30 and 40.
Thereafter, a pair of supporting bars 60 are connected back to back to each other by having the raised portions 604A, 606A and 608A on one of the bars into the recessed portions 604B, 606B and 608B respectively with a narrow spacing left between the main bodies thereof as shown in Figure 3. Then each pair of supporting bars 60 thus connected are disposed on the side surfaces of the associated interconnected first and second side plates 30 and 40 and the intermediate locking member 96 fixed thereto with the notches 600 and 602 thereon fitted onto the lateral surfaces of the mating source and load terminals 10 and 20 respectively and with front surfaces of side plate flush with the lateral surface of the adjacent supporting bar 60. Following this a screw 92 is threaded into the through hole 610 on each of the connected supporting bars 60 with a spring washer 94 interposed therebetween and then screw threaded into the threaded holes 962 and 964 respectively. Thus the pair of connected supporting bars 60 are fixed to each of the intermediate locking members 86 whereupon the assembling operation is completed.
The resulting structure is shown in Figure 3. From the foregoing it is seen that, the present invention provides a terminal assembly for a circuit interrupter very easily assembled because a plurality of pairs of opposite source and load terminals carried between associated first and second side plates to be connected together into a unitary structure with the first and second side plates and then a pair of bolts extend through the unitary structure sandwiched by a pair of metallic plates to maintain the unitary structure rigid. Further a pair of supporting bars bear an end portion of each pair of opposite source and load terminals to prevent those terminals from shifting due to a magnetic force developed thereon. This measure is effective for preventing associated equipments from damaging.

Claims

1. A terminal assembly for a circuit interrupter comprising a plurality of source terminals (10), one for each phase of the circuit interrupter, a plurality of load terminals (20) disposed opposite the source terminals (10) respectively, a plurality of pairs of first and second side plates (30, 40) each having in a front surface thereof a pair of parallel grooves (300, 400, 302, 402) for fitting onto lateral surfaces of the opposite source and load terminals respectively, and bolts (78, 80) extending through the first and second side plates to hold these and the terminals in position, characterised by a respective supporting bar (60) for fixing end portions of each pair of opposite source and load terminals.

2. A terminal assembly for a circuit interrupter as claimed in claim 1 wherein a pair of metallic plates (70, 72) are disposed in contact relationship on the outer sides of the outermost ones of the first and second side plates (30, 40), and the plurality of bolts (78, 80) extend through the pair of metallic plates (70, 72) along with the first and second side plates (30, 40).

3. A terminal assembly for a circuit interrupter as claimed in claim 1 or 2 wherein each of the source and load terminals (10, 20) includes on either of lateral surfaces thereof a recessed (104, 204) and a raised (108, 208) portion respectively and each of the first and second side plates (30, 40) has on the front surface a raised (306, 406) and a recessed (310, 410) portion capable of being fitted into and onto the recessed and raised portions on the mating lateral surfaces of the source and load terminals (10, 20) respectively.

4. A terminal assembly for a circuit interrupter as claimed in any of claims 1 through 3 wherein each pair of the first and second side plates (30, 40) are connected back to back to each other and disposed between one pair of the opposite source and load terminals (10, 20) for one of the phases of the circuit interrupter and another pair of the opposite source and load terminals (10, 20) for an adjacent one of the phases.

5. A terminal assembly for a circuit interrupter as claimed in any of claims 1 to 4 wherein each supporting bar (60) is disposed to be contacted by each of the lateral surfaces of the pair of opposite source and load terminals (10, 20) and includes a groove (600) fitted onto each of the lateral surfaces of either of the opposite source and load terminals (10, 20).

6. A terminal assembly for a circuit interrupter as claimed in claim 5 wherein each supporting bar (60) disposed on the outermost side is fixedly secured to an associated one of the pair of metallic plates (70, 72) through a lateral locking metallic member (86).

7. A terminal assembly for a circuit interrupter as claimed in claim 5 or 6 wherein one pair of the supporting bars (60) are disposed between one of the phases of the circuit interrupter and the adjacent phase thereof and fixed secured to the associated pair of the first and second side plates (70, 72) through an intermediate locking metallic member (96).